The present invention relates generally to a system for aiding in the timing of a fuel injection engine; and more particularly, to such a system including a piezoelectric transducer mounted on the fuel line for an engine cylinder for monitoring and sensing the fuel injection into the engine. The inventive transducer may also be conveniently utilized to determine engine RPM.
A number of devices are known which provide a sensing mechanism for sensing the fuel applied through a fuel line to a fuel injection engine. One such basic system is shown in U.S. Pat. No. 3,327,526, wherein a sensing device is positioned around the fuel line and comprises a microswitch which is caused to open and close in response to the surge of fuel through the fuel line. Another device for sensing the fuel injection to an engine is disclosed in U.S. Pat. No. 3,511,088, wherein a piezoelectric transducer or alternatively, a pressure sensitive transistor, is positioned to be actuated to develop a signal in response to the pressure developed as fuel is injected through the fuel line into the engine cylinder.
For one reason or another, the prior art devices known to the applicant have not been successful in providing a commercially viable product of the type described. The prior art devices just do not function properly in their operating environment.
Accordingly, it is the principal object of the present invention to provide a new and improved device for monitoring and sensing the charge of a fuel applied to a fuel injection engine.
It is another object of the present invention to provide a fuel injection monitoring and sensing device which is reliable in operation and provides a satisfactory signal representative of the fuel being injected to the associated engine, and which signal may be detected over engine vibrations and spurious noise.
It is another object of the present invention to provide a fuel injection monitoring and sensing device which may be conveniently mounted on a fuel injection line either in original manufactured equipment (OEM) or as a retrofitted device.